I hacked together a first, unfinished, largely untested prototype converter. This goes into the base directory of https://sourceforge.net/p/pdl/pdl-book/ci/master/tree/ as make_epub.pl:
#!/usr/bin/env perl
use v5.36;
use strict;
use warnings;
use Carp;
use App::Pod2Epub;
#use Archive::Zip;
use GD;
use MIME::Base64;
use English;
my $parser = App::Pod2Epub->new();
my @full;
my @subfiles;
{ # Read and parse TOC pod
my @lines = _readFile('PDL/Book.pod');
my $istoc = 0;
foreach my $line (@lines) {
if($line =~ /^\=over/) {
$istoc = 1;
#push @full, $line;
next;
} elsif($line =~ /^\=back/) {
$istoc = 0;
#push @full, $line;
next;
} elsif($istoc && $line =~ /^\=item/) {
my $subfile = '';
if($line =~ /\<(.+?)\|/) {
$subfile = $1;
$line =~ s/.*\>\ //;
$subfile =~ s/\:\:/\//g;
$subfile .= '.pod';
if(!-f $subfile) {
warn("$subfile does not exist");
} else {
push @subfiles, $subfile;
}
}
push @full, $line;
next;
}
push @full, $line;
}
push @full, '';
}
{ # Process chapters
foreach my $subfile (@subfiles) {
my @lines = _readFile($subfile);
foreach my $line (@lines) {
if($line =~ /^\=for\ html/) {
if($line =~ /\<img.*src\=\"(.+?)\"/) {
my $img = 'PDL/Book/' . $1;
if(-f $img) {
my $imgdata = _slurpBinFile($img);
$imgdata = encode_base64($imgdata, '');
my $imggd = GD::Image->new($img);
my ($width, $height) = $imggd->getBounds();
my $realline = '=for html <img width="' . $wid
+th . '" height="' . $height . '" src="data:image/png;base64, ' . $img
+data . '"/>';
push @full, $realline;
} else {
warn("Missing image $img in file $subfile");
push @full, "Missing image: $img";
}
next;
} else {
warn("Unknown 'for html' tag: $line in $subfile");
next;
}
}
push @full, $line;
}
push @full, '';
}
}
{ # Write complete POD file
open(my $ofh, '>', 'complete_book.pod') or croak($!);
foreach my $line (@full) {
print $ofh $line, "\n";
}
close $ofh;
}
if(0){ # Convert file to epub
open(my $ifh, '<', 'complete_book.pod') or croak($!);
open(my $ofh, '>', 'complete_book.epub') or croak($!);
binmode $ofh;
$parser->output_fh($ofh);
$parser->parse_file($ifh);
close $ifh;
close $ofh;
}
`pod2epub complete_book.pod -o complete_book.epub`;
#{ # Add images to ZIP file
# my $zip = Archive::Zip->new('complete_book.epub');
# foreach my $img (@images) {
# $zip->addFile('PDL/Book/' . $img => $img);
# }
# $zip->overwrite();
#}
sub _readFile($fname) {
my @lines;
open(my $ifh, '<', $fname) or croak($!);
while((my $line = <$ifh>)) {
chomp $line;
push @lines, $line;
}
close $ifh;
return @lines;
}
sub _slurpBinFile($fname) {
# Read in file in binary mode, slurping it into a single scalar.
# We have to make sure we use binmode *and* turn on the line termi
+nation variable completly
# to work around the multiple idiosynchrasies of Perl on Windows
open(my $fh, "<", $fname) or croak("$ERRNO");
local $INPUT_RECORD_SEPARATOR = undef;
binmode($fh);
my $data = <$fh>;
close($fh);
return $data;
}
Basically, it concatenates all chapters, and inlines all images. There's a lot more to do to make it pretty and more readable (especially the code sections) and fix some encoding issues. But i do get a mostly usable book with chapters, subchapters, pretty pictures and about 226 pages (default font size on my Boox ereader), including a chapter called "POD ERRORS" at the very end ;-)
Also, i still need to add all the .pl files as their own chapter at the very end of the book, so it's a COMPLETE reference.
Edit: Forgot to say, this is a work in progress, and more posts will follow. But it's a good start for what is, for me, equivalent to a "My First Epub generator" picture book ("with simple, large letters for a first forray into the world of written words")...
